Regressive Prediction Is the Best Way to Forecast Sports Outcomes: Evidence from Brazilian Soccer

摘要

We illustrate through a case study that regressive prediction is the best method to forecast sports outcomes. By taking predictions of promotion to first division soccer from a mathematician from one of the most famous sports websites in Brazil, we show that making Bayesian updates is misleading when we expect regression to the mean. The expert failed to realize that the more extreme the results are, the more regression is expected, because extremely good scores suggest very lucky days.